Etching apparatus



Nov. 11 1924.

V. C. RONNING ETCHING APPARATUS Filed Aug. 25. 1920 2" Sheets-Sheet 1 Patented Nov. ll, 1924-,

VICTOR C. RUNNING, OF NEW YORK, N. Y., ASSIGNOR 'lO AMERICAN ETCHING MACHINE CORPORATION, A CORPORATION OF NEW YOIRJL ETCHING APPARATUS.

Application fined August 25, 1920. Serial No. 406,040.

To all whom it may concern:

Be it known that I, VICTOR O. RONNING, a citizen of the United States, and a resident of the borough of Manhattan, city, county, and State of New York, have invented cert ain new and useful Improvements in Etching Apparatus, of which the following is a specification.

This invention relates to improvements in etching apparatus.

The process of etching with acid is accelerated'and improved in proportion to the number 'of the particles of the acid which can be brought into contact with the surface to be etched in the unit of time, that is, the more the etching liquid is moved the better the result. In etching metals with acids an insulficient movement of the latter causes not only a prolongation of the time of etching by forming layers poor in acid lying over the surface to be etched, but the oXid being irregularly formed on the metal and protecting the metal partially from the action of the acid, influences in a disadvantageous manner the uniformity of the etching, a circumstance which, where the elements are very delicate, directly deteriorates the equalityv of the product.

It will be seen, therefore, that devices of the type which cause a single wave to contact with the plate, as for example the oscillating movement of the etching trough or the reciprocating movement of a single wa'veeproducing device through the acid are not therefore effective. On the other hand devices which violently agitate the bathor cause a spraying, atomizing or violent splashing of the liquid against the plate cause the various particles of the acid to reach the plate in different phases or with difierent degrees of speed and these devices are also ineffective to etch plates with the uniformity in quality which may be obtained when the particles of acid reach the plate'in substantially the same phase.

One of the objects of this invention is to produce an apparatus in which a very large proportion of the acid particles of the bath will be moved and brought into contact with the plate in a unit of time and furthermore the various acid particles of this large quantity of thoroughly moved and distributed acid will be caused to move against the plate in substantially the same phase or with a uniform degree of speed, thus enabling the production of etched printing plates, half-tones and the like with greater accuracy of detail and better quality than has heretofore been possible with either type of machine above referred to, and also greatthe area of contact of any adjacent wave,

and to thisend'l provide a series of equallyspaced wave-producing members which have a common movement and are so moved to an extent substantially equal to the distance between adjacent wave-producing members.

Another object of my invention is to prevent splashing ancl to produce a downward suction in the bath between adjacent wave crests and a sucking in of the air in the pockets formed between adjacent wavecrests. To this end, the bottom edges of the series of wave-producing members are uniformly spaced from the bottom of the tank a predetermined distance, and I find that in order to procure the best results, the bottom edges of the waveproducing members should be so spaced from the bottom of the tank a distance substantially equal to the space between the top edges of the wave-producing members and the surface. of the plate to be etched.' When a series of wave-producing members are thus equally spacedfrom each other and when the top and bottom edges of the wave-producing members are'spaced substantially equi-distant from'the surface of the plate and the bottom of the tank, a downward suction in the liquid and air is produced between the adjacent waves which will remove particles which have been released by the acid without undercutting or otherwise injuriously afiecting the delicate parts of the plate, and the wave lengths being substan tially equal and the crest of each wave having a movement substantially equal to a wavelength there will be substantially no overlapping of the areas of contact produced by the adjacent waves.

l/Vith these and other objects in view the invention comprises the combination of members and arrangement of parts so combined as to co-act and cooperate with each other in the performance of the functions and the accomplishment of the results here in contemplated, and comprises in one of its adaptations the species or preferred form illustrated in the accompanying drawings, in which:

Fig. 1 is a longitudinal section. of'an apparatus embodying myinvention on the line 11 of Fig. 2.;

Fig 2. is.- a section on. the line 2-2. of Fig. l.;.

Fig-.. 3: is; at view ofith'e machine. in. side elevation, part. of the skeletonof; the: frame beingbroken awayrtotmore clearly illustrate the mechanism for actuating the agitators;

Referring now to-these drawings which illustrate a preferredembodiment of my invention, 1 is a receptacle or bath container which is supported in a suitable frame 2 preferably having legs 3 and containing a suitable etching liquid The plate or plates 4 are'supported :in'any suitable mannerface downward above the level of the etching liquid. As illustrated more especially in Fig. 2, a plurality of plates-4t are supported on a series of. plate supports 5, 6 and '7, the

central plate support 6-being a doublesupport provided on opposite sides with flanges or shoulders 6 and 6 respectively and the side plate supports 5 and 7 respectively having flanges or shoulders 5 and '7 respectively at one side only thereof. These plate supports are in turn supported at opposite ends on ribs 1 formed as shown integral with the'bath container or receptacle 1. ithin the container 1 and equally spaced from each other are a plurality of wave producing members 8, and in the embodiment of my invention shown I have illustrated a series of five of such wave-producing members which, as illustrated, are mounted tomove together or in common in a pair of frame members 9.

Each of these wave-producing members preferably have rectilinear top and bottom edges to produce'unbroken. waves, and comprises; av slat which extends without interruption transversely across the receptacleor container from side toside thereof, so as to extend over any area of a plate or plates to be etched. These equally spaced slats 8 are moved together. by the framememberst) a distance substantially equal to the distance between adjacent wave producing members. Any suitable means may be provided for oscillating the frame members 9 to move these Wave producing members 8' and as shown the" frame members-9 are eachpro vided with uprights 10 which extend above the top of the container or receptacle 1 and are fixed by connecting members 11 to shafts 12, which shafts 12 are moved back and forth or reciprocated at opposite sides of the tank in bearings 13 and these connecting members 11 are provided with depending forked parts 11'" to which is pivoted at 1 1 one of the ends of links 15 which are pivotally connected at their opposite ends to crank wheels 16 fast on shaft 16 and which are provided with gear teeth 17 meshing with gears 18 fast on a shaft 19 which is located by the intermeshing of apinion. 20 fast on said shaft 19 witha worm 21 on the shaft 22 of the. motor 23, which motor is supplied with electrical energy from any suitable source. not shown. and. as illustrated initheem'bodiment shown it is suitably supported on a platform 3 on the'legsx The levelv of the etching; liquid. is; preferably substantially flush with. the top edges of the wave-producing members 8. These members 8 are preferably, as shown, spaced a predetermined distance from the bottom of the tank 1 and I find that inorder to procure thebest results the bottom edges of the said wave producing members 8 should be so spaced from the bottom of the tank a distance substantially equal to the space between the top edges of the said wave producing members and thesurface of the plate to be etched- In practice, I find that the distance between the bottom edges of said wave producing members and the bottom: of the tank and the topedges of the wave producing members and the Surface of the plate to be etched will be approximately three-eighths of an inch each.

When a. plurality or series of wave producing members are as above described equally spaced from each other and when the top and bottom edges of such wave producing members are spaced substantially equi-distant but in proximity to the surface of the plate and the bottom of the-tank, a downward suction in the liquid and. air will be produced between adjacent waves and this suction will remove particles which have been previously released by the acids without undercutting or otherwise injuriously affecting the delicate parts of the plate, and the said wave producingmembers having a movement substantially equal to a wave length produced by thesaid wave producing members, no overlappingof the areas of contact by adjacent waves will occur. It will be obvious that splashing of the etching liquid between the adjacent waveproducing members will be obviated.

' From the above it will be seen thatlhave produced an apparatus in which. a: very large proportion of the acid particles of a bath will be moved and brought into-eontact with the-plate in a unit of t-ime,,and

furthermore that the various acid particles of this large quantity of moving acid will be caused to move against the plate in substantially the same phase, or with a uniform degree of speed, thus producing etched printing plates, half-tones and the like with greater accuracy of detail and better quality than has heretofore been possible with types of machines which are not so capable of moving a large proportion of acid in a unit of time and also causing such particles of such acid to contact with the plate to be etched in substantially the same phase or with substantially uniform degrees of speed.

Having described my invention I claim 1. Etching apparatus embodying a liquid receptacle, means for supporting a plate above and in proximity to an etching bath in said receptacle; a series of Wave producing members spaced from each other to produce a predetermined wave length and means for causing the said wave-producing members to be moved a distance substantially equal to the length of the wave, said wave-producing members having the bottom edges spaced from the bottom of the bath receptacle a distance substantially equal to the space between the top edges of such members and the plate to be tched.

2. Etching apparatus embodying a liquid receptacle, means for supporting a plat-e above and in proximity to an etching bath in said receptacle; a series of wave producing members having substantially rectilinear top edges and spaced from each other to produce a predetermined wave length and means for causing the said wave-producing members to be moved a distance substantially equal to the length of the wave, said wave-producing members having the bottom edges spaced from the bottom of the bath receptacle a distance substantially equal to the space between the top edges of such members and the plate to be etched.

3. Etching apparatus embodying a liquid receptacle, means for supporting a plate above and in proximity to an etching bath in said receptacle; a series of wave producing members having substantially rectilinear top and bottom edges and spaced from each other to produce a predetermined wave length and means for causing the said waveproducing membersto be moved a distance substantiallyequal to the length of the wave, said wave-producing members having the bottom edges spaced from the bottom of the bath receptacle a distance substantially equal to the space between the top edges of such members and the plate to be etched.

4L. Etching apparatus embodying, a liquid receptacle having an etching bath contained therein, a plate supported in proximity to the level of said bath, a series of equally spaced wave-producing members movable within the bath and having substantially rectilinear top and bottom edges, the top edges being disposed substantially flush with the level of the etching bath and spaced from the plate a predetermined distance, the bottom edges being spaced from the bottom of the bath a distance substantially equal to the distance between the top edge and the plate, and means for moving said wave-producing members. i

5. Etching apparatus embodying a liquid receptacle, means for supporting) plate above and in proximity to an etching bath in said receptacle, a series of wave-producing members movable together within the bath to cause a series of unbroken waves to contact with the plate, said wave-producing members comprising a series of verticallydisposecl continuous slats suitably spaced from each other to form a series of transversely-disposed inter-slat chambers extending transversely across and within the etching bath and means for moving said waveproducing members within the bath.

6. Etching apparatus embodying a liquid receptacle, means for supporting a plate above and in proximity to an etching bath in said receptacle, a series of wave-producing members movable together within the bath to cause a series of unbroken waves to con tact with the plate, said Wave-producing members comprising a series of continuous vertically-disposed and unobstructed slats suitably spaced from each other to form a series of transversely-disposed inter-slat chambers and means for moving said wave producing me1nbers within the bath.

7. Etching apparatus embodying a liquid receptacle, means for supporting a plate above and in proximity to an etching bath in said receptacle, a series of wave-producing members movable together within the bath to cause a series of unbroken waves to contact with the plate, said wave-producing members comprising a series of continuous vertically-disposed and unobstructed slats suitably spaced from each other to form a series of transversely-disposed inter-slat chambers, said slats having rectilinear top edges substantially flush with the level of the etching liquid and means for moving said wave-producing members within the bath.

In Witness whereof, I have signed my name to the foregoing specification in the presence of two subscribing witnesses.

VICTOR C. RONNING. W'itnesses HELEN V. WHInDn-R, STALLO VIN'roN. 

